1. Field of the Invention
A process for pulse combustion in a horizontal pulse combustor having a fuel inlet valve, an air inlet valve, a combustion chamber, and a plurality of downstream combustion chamber branches each having a plurality of downstream exhaust tubes.
2. Description of the Prior Art
Pulsing combustion devices and processes are generally known to the art. Putnam et al., U.S. Pat. No. 4,314,444, discloses a two-stage apparatus for burning a fuel and a combustion-sustaining gas. A portion of fuel is burned in a first stage having pulse combustors. The remaining fuel is burned in a second combustion stage with gas that is aspirated using backflow through an aerodynamic valve inlet. The '444 patent discloses a valveless pulse combustor in which the flow of gas in one direction is stronger than the flow of the gas in an opposite direction. The '444 patent teaches a plurality of pulse combustors wherein each pulse combustor has only one combustion chamber and only one outlet conduit. The second combustion stage has one combustion chamber with a multiplicity of exhaust tubes. The '444 patent teaches a vertical arrangement for the heating apparatus.
Kitchen, U.S. Pat. No. 4,241,723, discloses a pulse combustion heater having a combustion chamber and at least one exhaust pipe forming a resonant system with a chamber. The combustion chamber is in the form of a one-piece bronze casting having an internal cavity which is generally of flattened spherical shape.
Whitacre, U.S. Pat. No. 3,554,182, teaches a liquid heater, especially adapted for liquid submerged uses, for example for heating a swimming pool. The combustion generated is of the pulse type and the combustion chamber in which the fuel-air mixture is ignited has a body of material of high radiating potential, such as ceramic, which is heated in the combustion chamber and which radiates heat to the enclosing heat-conducting walls of the chamber in contact with the liquid to be heated.
Severyanin, Russian Pat. No. 826,137, discloses a pulsating combustion unit having an ignition chamber connected to an exhaust chamber through two resonance pipes. One of the resonance pipes has a length which exceeds the length of the other resonance pipe by 3 times to increase combustion efficiency. Combustion products reach the exhaust chamber in an anti-phase thus reducing sound radiation.
Davis, U.S. Pat. No. 4,637,792, describes a pulsing combustion device having a combustion chamber and a floating valve member mounted in reciprocal relation in the wall of the combustion chamber where reciprocation of the floating valve closes and opens communication through ports between the supply of a combustible mixture and the combustion chamber. The '792 patent teaches a single elongated combustion chamber burner shell which defines a combustion chamber. Davis, U.S. Pat. No. 4,651,712, teaches a pulsing combustion device having a combustion chamber with an inlet for a combustible mixture and an unvalved outlet open to the atmosphere for combustion gases. The '712 patent describes an elongated combustion chamber shell or burner shell which defines a combustion chamber. The combustible mixture is ignited and burned in a single combustion chamber.
Adams, U.S. Pat. No. 4,465,024, and Adams, U.S. Pat. No. 4,545,329, teach a water heater having a water tank with a water inlet, a water outlet, and an opening in the side wall of the tank. The combustion chamber assembly has a submergible portion which is adapted to fit within the opening in the tank side wall. The submergible combustion chamber portion comprises a single cylindrical elongated member having an open end and an opposite closed end. A plurality of curved fire tubes are joined to and extend from the closed end of the combustion chamber to a single flue. The Adams patents disclose power combustion systems where fuel and air are force fed to the point where combustion occurs.
Cook, U.S. Pat. No. 4,257,355, teaches a cold water inlet tube located in a horizontal position adjacent the bottom of a commercial water heater. The water heater has a tank formed of a cylindrical shell which is enclosed by a lower head and an upper head. A plurality of vertical flues are disposed inside the tank and extend from the end of the combustion chamber to a single flue. The system operates with a natural draft venting system and not a pulse combustion system.
Asakawa, U.S. Pat. No. 3,665,153, teaches an apparatus and method for heating water to generate steam or provide hot water. A burner is positioned in a combustion chamber having heat exchanger pipes passing from one end of the combustion chamber to a chimney. The combustion system operates with a natural draft venting system, not an acoustically tuned pulse combustion system.
Lovekin, U.S. Pat. No. 1,170,834, teaches a thermostatic valve mechanism which supplies gas to a burner of a heater. FIG. 1 of the '834 patent shows a single corrugated combustion chamber with a flue exiting from one end.